In A Nutshell

We’ve all heard that we only use about 10 percent of our brains. It’s an attractive idea: After all, we can blame our untapped brain power for our unrecognized potential. The problem is that it’s a myth; we already use pretty much 100 percent of our brain every day, and its amazing abilities are channeled into everything from deciding what’s for dinner to keeping our hearts going. The myth may have simply surfaced from a misunderstanding that we only know the function of about 10 percent of our brain cells—the others are still working, we’re just not sure how.

The Whole Bushel

It’s fun to think about what we would be capable of if we could harness all that untapped brain power. Telekinesis, maybe, or inventing the next great advance in technology. Seeing the future? Reading minds? After all, we only use about 10 percent of our brains now, and just look what we’re capable of. Right?

Not so much. With the help of medical technologies that allow scientists to monitor electrical activity in the brain, it’s been found that we use almost all of our brain on a daily basis, whether we realize it or not.

Different parts of the brain control different things. The temporal lobe processes hearing, speech, and language, while the cerebellum controls movements that we think are automatic, such as minute adjustments that allow us to keep our balance. The prefrontal lobe is the part of the brain that allows us to think ahead, make judgments, and weigh options.

That’s more than 10 percent right there.

And that’s not even taking into account the sections of the brain that are in constant communication. The prefrontal lobe works closely with the limbic system. While the limbic system is the more primal part of the brain that is responsible for our emotions, the prefrontal lobe helps us regulate those emotions and channel them in to a more proper response (ideally). The brain’s neurons are constantly firing electrical energy through our brains.

So where did the myth come from?

The definite source isn’t easily identifiable, but there are some likely culprits. In his 1908 book The Energies of Men, American psychologist William James made mention of the fact that we only seem to be using a small part of our mental resources.

Perhaps even more intriguing as a possible source for the myth is Wilder Penfield, a neurosurgeon from the Montreal Neurological Institute of McGill University. Penfield was researching a technique for curing epilepsy that involved damaging the part of the brain responsible for causing seizures. In order to determine whether or not this would be a viable treatment, he knew he had to see what other parts of brain function were controlled by the same part of the brain.

Because there are no pain receptors in the brain, Penfield could poke around in the brain of a fully conscious person. He found areas that were connected to stimulating memory, auditory hallucinations, visual hallucinations, and other noticeable functions. And he noted that about 10 percent of the brain could be connected to a “detectable event.”

But that’s still not taking into account the undetectable events that happen in the brain all the time, like communication between the left and right side.

Another possibility for the source of the myth comes from what we know about how the brain works. The brain is made up of neurons—which carry electrical information and impulses—and glial cells. About 10 percent of the brain is neurons, and the rest is a high percentage of these glial cells. These glial cells support the function of the neurons, but beyond that, science isn’t really sure what they do.

And science certainly hasn’t been able to tell is where the human consciousness is, leaving that mystery so far defined as a collaborative effort between brain cells.

Because we’re only really sure about what 10 percent of the brain’s cells actually do—the neurons—it’s also possible that the myth has been perpetuated by that number (and perhaps further perpetuated by the comfort we try to find in blaming our biology for our shortcomings).